An influx of mining investments throughout Latin America is bringing badly needed investment, but is also causing tensions in some communities, pitting those who see mines as job creators against those who view them as predatory, in some cases threatening scarce resources like water. Here in the Ocotlán valley in the southern Mexican state of Oaxaca, two outspoken opponents of a subterranean mine run by a small Canadian firm, Fortuna Silver Mines Inc., were killed in separate incidents in the past year. Dozens were beaten or threatened. Two local government officials who approved the mine, including the then-mayor, were killed by an anti-mining mob.

From 2006 to 2011, mining exploration investment in the region jumped 150% to $4.55 billion, top in the world and equal to one in every four dollars, according to the mining industry information company Metals Economics Group. The investments are creating jobs, roads and other benefits in some of the most neglected corners of the developing world. But it is also creating tensions in a region with a long and complicated history with mining.

A multi-party alliance to modernize Mexico’s economy will not discuss pending energy and tax reforms until an electoral spat between the opposition and the government is resolved, the head of the main leftist party said on Tuesday. Jesus Zambrano, chairman of the opposition Party of the Democratic Revolution (PRD), said there could be no talks on these reforms until the government had taken clear steps to punish those responsible for a vote-buying scandal in the Gulf state of Veracruz that was exposed this month.

“There won’t be (talks) about anything that is not to do with the political and legal … structure that will enable us to get out of this impasse,” he told Reuters in an interview. President Enrique Pena Nieto’s ruling Institutional Revolutionary Party, or PRI, has been forced on the defensive since the conservative National Action Party (PAN) put out recordings of PRI officials advocating the use of government funds to secure votes in Veracruz in elections due on July 7.

Mexico’s four-month-old administration on Wednesday appeared to overcome its first political crisis after opposition leaders said that they had largely settled their differences with the government. The agreement, which came after an emergency meeting of party heads, appears to put the government’s economic reform back on track in a turnaround that will doubtless ease investor concerns.

Billions of dollars have flowed into Mexico in recent months on hopes that centrist President Enrique Peña Nieto of the Institutional Revolutionary Party will push a series of reforms aimed at transforming Latin America’s second-largest economy into a more vibrant emerging market.